h8s-2169 Renesas Electronics Corporation., h8s-2169 Datasheet - Page 114

• Manufacturer Part Number: h8s-2169
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 3 MCU Operating Modes
3.3
3.3.1
The CPU can access a 64-kbyte address space in normal mode. The on-chip ROM is disabled.
Ports 1 and 2 function as an address bus, port 3 functions as a data bus, and part of port 9 carries
bus control signals. Clearing the ABW bit to 0 in the WSCR register makes port B a data bus.
3.3.2
The CPU can access a 16-Mbyte address space in advanced mode. The on-chip ROM is enabled.
After a reset, single-chip mode is set, and the EXPE bit in MDCR must be set to 1 in order to use
external addresses.
When the EXPE bit in MDCR is set to 1, ports 1, 2 and A function as input ports after a reset.
They can be set to output addresses by setting the corresponding bits in the data direction register
(DDR) to 1. Port 3 functions as a data bus, and part of port 9 carries bus control signals. Clearing
the ABW bit to 0 in the WSCR register makes port B a data bus.
3.3.3
The CPU can access a 64-kbyte address space in normal mode. The on-chip ROM is enabled.
After a reset, single-chip mode is set, and the EXPE bit in MDCR must be set to 1 in order to use
external addresses.
When the EXPE bit in MDCR is set to 1, ports 1 and 2 function as input ports after a reset. They
can be set to output addresses by setting the corresponding bits in the data direction register
(DDR) to 1. Port 3 functions as a data bus, and part of port 9 carries bus control signals. Clearing
the ABW bit to 0 in the WSCR register makes port B a data bus.
In this operating mode, the available amount of on-chip ROM in products with 64 kbytes or more
of ROM is limited to 56 kbytes.
Rev. 3.00 Jan 18, 2006 page 86 of 1044
REJ09B0280-0300
Mode 1
Mode 2
Mode 3
Operating Mode Descriptions